How long ago they were laid. How well they were stored. How many transfers during shipping. How your local grocer treated them.
And you might not eat a dozen eggs as soon as you bring them home from the store. So how do you know if an egg is still good to eat?
There is a simple test that takes just a minute to complete. Fill a bowl with water, at least three inches deep. Place the egg gently in the water. If it sinks and stays sunk, it’s good. If it floats, it might be more useful at a protest. If it sort of sinks, sort of floats, you had better eat it quickly to avoid having to take it to a protest. This test is so simple and so obvious, that some people have suggested instructions should be printed on the inside of every egg carton, like this:
